Electronic device with reworkable midplate attachment structures

Abstract

An electronic device may be provided with a display mounted in a display frame assembly that includes a plastic structure overmolded over a display frame. A housing midplate may be used to provide the electronic device with mechanical rigidity and strength, and may also be used as a sensor plane. For sensor plane applications, accurate placement and assembly of the midplate in the housing can be critical. The housing midplate may be accurately assembled to the display frame using connections formed using welded tabs, welded and screwed nuts, overmolded plastic heat stake structures, or overmolded plastic structures and adhesive. Rework and repair operations may be performed by disconnecting connections such as welds using cutting equipment, by using solvent to dissolve adhesive, by unscrewing welded nuts, or by removing heat stake structures. Following rework or repair, a fresh midplate and associated components may be attached to the display frame.

What is claimed is: 
     
       1. An electronic device, comprising:
 a housing; 
 a display; 
 a display frame that receives the display, wherein the display frame has first and second opposing sides; and 
 a midplate within the housing that is attached to the display frame with a weld, wherein the midplate extends behind the display from the first side of the display frame to the second side of the display frame. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the midplate has two parallel tabs separated by a slot and wherein the weld is formed between one of the two parallel tabs and the display frame. 
     
     
       3. The electronic device defined in  claim 2  wherein the display frame has a display frame tab that is welded to the midplate by the weld. 
     
     
       4. The electronic device defined in  claim 3  further comprising plastic overmolded over the display frame. 
     
     
       5. The electronic device defined in  claim 4  wherein the plastic and the display frame form a display frame assembly that is attached to the display with adhesive. 
     
     
       6. The electronic device defined in  claim 1  wherein the midplate has a tab, wherein the display frame has two parallel tabs separated by a slot, and wherein the weld is formed between one of the two parallel tabs of the display frame and the tab of the midplate. 
     
     
       7. The electronic device defined in  claim 6  further comprising plastic overmolded over the display frame to form a display frame assembly to which the display is attached with adhesive. 
     
     
       8. An electronic device, comprising:
 a housing; 
 a display; 
 a display frame that receives the display; 
 a midplate within the housing that is attached to the display frame with a weld; 
 a screw; and 
 a nut that is attached to the display frame with the screw, wherein the weld is formed between the nut and the midplate. 
 
     
     
       9. The electronic device defined in  claim 8  wherein the display frame has a tab, wherein a hole is formed in the tab, and wherein the screw passes through the hole. 
     
     
       10. The electronic device defined in  claim 9  wherein the midplate has a tab and wherein the weld is formed between the nut and the tab of the midplate. 
     
     
       11. The electronic device defined in  claim 10  further comprising a plastic structure that is overmolded over the display frame to from a display frame assembly that is attached to the display with adhesive. 
     
     
       12. An electronic device, comprising:
 a housing; 
 a display; 
 a display frame that receives the display; 
 a midplate within the housing; and 
 a plastic structure overmolded onto a portion of the midplate, wherein midplate is attached to the display frame with the plastic structure. 
 
     
     
       13. The electronic device defined in  claim 12  further comprising adhesive that attaches the display frame to the plastic structure. 
     
     
       14. The electronic device defined in  claim 13  wherein the portion of the midplate onto which the plastic structure is overmolded is a prong. 
     
     
       15. The electronic device defined in  claim 12  wherein the plastic structure has a heat stake that is received within an opening in the display frame. 
     
     
       16. The electronic device defined in  claim 15  wherein the portion of the midplate onto which the plastic structure is overmolded is a prong and wherein the display frame has a tab in which the opening is formed. 
     
     
       17. A method, comprising:
 mounting a display in an electronic device display frame having first and second opposing sides; and 
 attaching a housing midplate to the display frame using a permanent connection, wherein the housing midplate extends behind the display from the first side of the electronic device display frame to the second side of the electronic device display frame. 
 
     
     
       18. The method defined in  claim 17  further comprising:
 removing the permanent connection during repair operations on an electronic device containing the electronic device display frame. 
 
     
     
       19. The method defined in  claim 18  wherein the permanent connection comprises a weld between a tab on the electronic device display frame and the housing midplate. 
     
     
       20. The method defined in  claim 19  wherein removing the permanent connection comprises cutting away a tip portion of the tab to remove the weld from the electronic device display frame, the method further comprising welding a replacement midplate to the tab after removing the weld.